The present invention relates to a method of manufacturing an electronic device and a device for manufacturing the same, and more particularly to a method of manufacturing an electronic device manufactured through a process of giving a droplet of a liquid including a formation material of a member that constitutes the electronic device onto a substrate and a device for manufacturing the electronic device.
Up to now, known electron emission elements are roughly classified into two kinds of a thermionic electron emission element and a cold cathode electron emission element. The cold cathode electron emission element includes a field emission type (hereinafter referred to as xe2x80x9cFE typexe2x80x9d), a metal/insulating layer/metal type (hereinafter referred to as xe2x80x9cMIM typexe2x80x9d), a surface conduction type electron emission element, etc.
Examples of the FE type have been disclosed in xe2x80x9cField Emissionxe2x80x9d of Advance in Electron Physics, 8,89 (1956) by W. P. Dyke and W. W. Dolan, xe2x80x9cPhysical Properties of thin-film field emission cathodes with molybdenum conesxe2x80x9d of J. Appl. Phys., 47,5248 (1976), by C. A. Spindt, etc.
Examples of the MIM type have been disclosed in xe2x80x9cOperation of Tunnel-Emission Devicesxe2x80x9d of J. Appl., Phys., 32,646(1961), by C. A. Mead, etc.
Examples of the surface conduction type electron emission element have been disclosed in Radio Eng. Electron Phys., 10, 1290(1965) by M. I. Elinson, etc.
The surface conduction type electron emission element utilizes a phenomenon in which electron emission occurs by allowing a current to flow into a small-area thin film formed on an insulating substrate in parallel to a film surface.
As the surface conduction type electron emission element, there have been reported a surface conduction type electron emission element using an SnO2 thin film by M. I. Elinson, etc., a surface conduction type electron emission element using an Au thin film [G. Dittmer: xe2x80x9cThin Solid Filmsxe2x80x9d, 9,317 (1972)], a surface conduction type electron emission element using an In2O3/SnO2 thin film [M. Hartwell and C. G. Fonstad: xe2x80x9cIEEE Trans. ED Conf.xe2x80x9d, 519(1975)], a surface conduction type electron emission element using a carbon thin film [xe2x80x9cVapor Vacuumxe2x80x9d of Volume 26, No. 1, p 22 (1983), by Hisashi Araki, et al.], etc.
As a typical example of those surface conduction type electron emission elements, the structure of the above-mentioned element by M. Hartwell is schematically shown in FIG. 25. In the figure, reference numeral 2001 denotes a substrate. Reference numeral 2004 denotes an electrically conductive film that is formed of a metal oxide thin film formed in an H-shaped pattern, etc., where there is formed an electron emission portion 2005 through an electrifying process called xe2x80x9celectrification formingxe2x80x9d which will be described later. In the figure, an interval L between the element electrodes is set to 0.5 to 1 mm, and Wxe2x80x2 is set to 0.1 mm.
In those surface conduction type electron emission elements, it is general that the electron emission portion 2005 is formed on the electrically conductive film 2004 through the electrifying process which is called xe2x80x9celectrification formingxe2x80x9d before the electron emission is conducted. In other words, the electrification forming is a process in which a voltage is applied to both ends of the electrically conductive film 2004 so that the electrically conductive film 2004 is electrified, to thereby locally destroy, deform or affect the electrically conductive film 2004 to change the structure, thus forming the electron emission portion 2005 which is in an electrically high-resistant state. A fissure occurs in a part of the electrically conductive film 2004 on the electron emission portion 2005, and electrons are emitted from a portion close to the fissure.
The above surface conduction type electron emission element is advantageous in that a large number of elements can be arranged over a large area, because the structure is simple. Accordingly, various applications for making the best use of that advantage have been researched. For example, the surface conduction type electron emission element is applied to a charge beam source or an image forming apparatus such as a display device.
Up to now, as an example in which a large number of surface conduction type electron emission elements are arranged, there is an electron source in which the surface conduction type electron emission elements are arranged in parallel with each other, and a large number of lines obtained by connecting both ends (both of element electrodes) of the respective surface conduction type electron emission elements to each other by wirings (also called xe2x80x9ccommon wiringsxe2x80x9d), respectively, are arranged (also called xe2x80x9cladder-type arrangementxe2x80x9d) (for example, Japanese Patent Application Laid-open No. 64-31332, Japanese Patent Application Laid-open No. 1-283749 and Japanese Patent Application Laid-open No. 2-257552).
Also, in particular, in the display device, a plate-type display device similarly to the display device using the liquid crystal can be provided, and there has been proposed a display device that combines an electron source in which a large number of surface conduction type electron emission elements are arranged with a fluorescent material that emits a visible light with being irradiated with an electron ray from the electron source (U.S. Pat. No. 5,066,883).
Also, FIG. 26 is a perspective view showing the structure of an electron emission element disclosed in Japanese Patent Application Laid-open No. 2-56822. In the figure, reference numeral 3001 denote a substrate; 3002 and 3003, element electrodes; 3004, an electrically conductive film; and 3005, an electron emission portion. There have been proposed various methods of manufacturing the electron emission element. For example, the element electrodes 3002 and 3003 are formed on the substrate 3001 through a general vacuum evaporation technique or a photolithgraphy technique. Then, the electrically conductive film 3004 is formed through a dispersion coating method. Thereafter, a voltage is applied to the element electrodes 3002 and 3003 to conduct an electrifying process, thereby forming the electron emission portion 3005.
However, the conventional method of manufacturing the electron emission element suffers from such defects that the number of processes are large, it is difficult to form the electron emission elements on the large area through the existing technique, a special and expensive manufacturing device is required and the production costs are high, because the semiconductor process is mainly conducted in the conventional method.
Under the above circumstances, the present applicants have studied an electron source substrate obtained in such a manner that a solution containing a metal is ejected onto a substrate in the state of a droplet to form element electrodes and element films, and the elements are arranged on an insulating substrate in matrix.
For example, Japanese Patent Application Laid-open No. 8-171850 discloses a method of manufacturing the element electrode and the element film using an ink jet method, and also Japanese Patent Application Laid-open No. 9-069334 and EP-A-0717428 disclose a method in which a liquid droplet is supplied onto a substrate disposed on a stage through an ink jet method while the stage is scanned, to thereby form the element film.
On the other hand, as an example in which an electronic device other than the electron emission element and the electron source is manufactured through the ink jet method, there has been disclosed a method of manufacturing a color filter by using the ink jet method in Japanese Patent Application Laid-open No. 8-327816.
However, in the method of manufacturing the above-described electron emission element by using the ink jet method and the manufacturing device thereof, since there is provided no correcting mechanism for correcting a position to which a droplet is given in accordance with the deformation of the substrate (distortion and unevenness of the thickness of the substrate) accompanied by the large-sized electron source substrate, it is difficult to improve the yield in manufacturing the large-area electron source substrate and the image forming apparatus using that substrate, thereby resulting in the high production costs.
Also, not only in the manufacture of the electron emission element or the like, but also in the manufacture using the above-described ink jet method of the color filter, since there is provided no correcting mechanism for correcting a position to which a droplet is given in accordance with the deformation of the substrate (distortion and unevenness of the thickness of the substrate) accompanied by the large-sized electron source substrate, it is difficult to improve the yield in manufacturing, thereby resulting in the high production costs.
An object of the present invention is to provide a manufacturing method and a manufacturing device which are capable of forming a member that constitutes an electronic device on desired plural portions of a substrate with a high accuracy.
Also, another object of the present invention is to provide a manufacturing method and a manufacturing device which are capable of forming electronic devices on a plurality of substrates with a high reproducibility.
Further, still another object of the present invention is to provide a manufacturing method and a manufacturing device which are capable of forming a plurality of electronic devices uniform in characteristic on a substrate.
Further, yet still another object of the present invention is to provide a manufacturing method and a manufacturing device which are capable of manufacturing an electron source having a plurality of electron emission elements uniform in electron emission characteristic.
Further, yet still another object of the present invention is to provide a manufacturing method and a manufacturing device which are capable of easily manufacturing an electronic device having a uniform characteristic at low costs.
In order to achieve the above objects, the present invention is structured as follows:
According to the present invention, there is provided a method of manufacturing an electronic device including a step of giving a droplet of a liquid containing a formation material of a member that constitutes the electronic device to a plurality of portions on a substrate while the substrate and a droplet ejecting portion are moved relatively in an in-surface direction of the substrate, characterized in that the droplet is given while a position on a droplet given surface to which the droplet is given is corrected in accordance with the distribution of distances between the ejecting portion and the droplet given surface on the substrate which occurs when the substrate and the ejecting portion are relatively moved.
Also, according to the present invention, there is provided a method of manufacturing an electron source having a plurality of electron emission elements, characterized in that there is provided a step of giving a droplet of a liquid containing a formation material of an electrically conductive member that constitutes the electron emission element to a plurality of portions on a substrate while the substrate and a droplet ejecting portion are moved relatively in an in-surface direction of the substrate, and in that the droplet is given while a position on a droplet given surface to which the droplet is given is corrected in accordance with the distribution of distances between the ejecting portion and the droplet given surface on the substrate which occurs when the substrate and the ejecting portion are relatively moved.
Further, according to the present invention, there is provided a method of manufacturing an electron source having a plurality of electron emission elements with an electrically conductive film having an electron emission portion between a pair of electrodes, characterized in that the formation of the electrically conductive film includes a step of giving a droplet of a liquid containing a formation material of the electrically conductive film to a plurality of portions on a substrate while the substrate and a droplet ejecting portion are moved relatively in an in-surface direction of the substrate, and in that the droplet is given while a position on a droplet given surface to which the droplet is given is corrected in accordance with the distribution of distances between the ejecting portion and the droplet given surface on the substrate which occurs when the substrate and the ejecting portion are relatively moved.
Still further, according to the present invention, there is provided a method of manufacturing an electron source having a plurality of electron emission elements with an electrically conductive film having an electron emission portion between a pair of electrodes, characterized in that the formation of the pair of electrodes and the electrically conductive film includes a step of giving the respective droplets of a liquid containing a formation material of the pair of electrodes and a liquid containing a formation material of the electrically conductive film to a plurality of portions on a substrate while the substrate and a droplet ejecting portion are moved relatively in an in-surface direction of the substrate, and in that the droplets are given while a position on a droplet given surface to which the droplets are given is corrected in accordance with the distribution of distances between the ejecting portion and the droplet given surface on the substrate which occurs when the substrate and the ejecting portion are relatively moved.
Yet still further, according to the present invention, there is provided a method of manufacturing an electron device or electron source in which the droplets are given while a distance between the ejecting portion and the droplet given surface on the substrate is detected, and a position on the droplet given surface to which the droplet is given is corrected on the basis of the detection result.
Also, the above-described manufacturing method according to the present invention includes:
that the detection of the distance includes a step of measuring the distances between the ejecting portion and all of the droplet given portions within the droplet given surface;
that the detection of the distance includes a step of measuring a distance between the ejecting portion and a specific portion of the droplet given surface; or
that the detection of the distance includes a step of measuring a distance between the ejecting portion and a specific portion of the droplet given surface, and a step of calculating the distances between the ejecting portion and all of the droplet given portions within the droplet given surface on the basis of the measurement result.
Also, the above-described manufacturing method according to the present invention includes:
that the correction of the position to which the droplet is given is made by maintaining the distance between the ejecting portion and the droplet given surface on the substrate constant;
that the correction of the position to which the droplet is given is made by changing a timing at which the droplet is ejected from the ejecting portion in accordance with the distribution of the distances between the ejecting portion and the droplet given surface on the substrate; or
that the correction of the position to which the droplet is given is made by changing an inclination of the substrate in accordance with the distribution of the distances between the ejecting portion and the droplet given surface on the substrate.
Yet still further, according to the present invention, there is provided a method of manufacturing an electronic device including a step of giving a droplet of a liquid containing a formation material of a member that constitutes the electronic device to a plurality of portions on a substrate while the substrate and a droplet ejecting portion are moved relatively in an in-surface direction of the substrate, characterized in that the droplet is given while a droplet given position on the substrate surface is corrected in accordance with the distribution of thicknesses of the substrate.
Yet still further, according to the present invention, there is provided a method of manufacturing an electron source having a plurality of electron emission elements, characterized in that there is provided a step of giving a droplet of a liquid containing a formation material of an electrically conductive member that constitutes the electron emission element to a plurality of portions on a substrate while the substrate and a droplet ejecting portion are moved relatively in an in-surface direction of the substrate, and in that the droplet is given while a position on a substrate surface to which the droplet is given is corrected in accordance with the distribution of a thickness of the substrate.
Yet still further, according to the present invention, there is provided a method of manufacturing an electron source having a plurality of electron emission elements with an electrically conductive film having an electron emission portion between a pair of electrodes, characterized in that the formation of the electrically conductive film includes a step of giving a droplet of a liquid containing a formation material of the electrically conductive film to a plurality of portions on a substrate while the substrate and a droplet ejecting portion are moved relatively in an in-surface direction of the substrate, and in that the droplet is given while a position on the substrate surface to which the droplet is given is corrected in accordance with the distribution of thicknesses of the substrate.
Yet still further, according to the present invention, there is provided a method of manufacturing an electron source having a plurality of electron emission elements with an electrically conductive film having an electron emission portion between a pair of electrodes, characterized in that the formation of the pair of electrodes and the electrically conductive film includes a step of giving the respective droplets of a liquid containing a formation material of the pair of electrodes and a liquid containing a formation material of the electrically conductive film to a plurality of portions on a substrate while the substrate and a droplet ejecting portion are moved relatively in an in-surface direction of the substrate, and in that the droplets are given while a position on a droplet given surface to which the droplets are given is corrected in accordance with the,distribution of thicknesses of the substrate.
Yet still further, according to the present invention, there is provided a method of manufacturing an electronic device or an electron source having a plurality of electron emission elements characterized in that the droplet is given while the thickness of the substrate is detected, and a droplet given position on the substrate surface is corrected on the basis of the detection result.
Also, the above-described manufacturing method according to the present invention includes:
that the detection of the thickness includes a step of measuring the thicknesses of all of the droplet given portions on the substrate surface;
that the detection of the thickness includes a step of measuring a thickness of a specific portion on the substrate surface; or
that the detection of the thickness includes a step of measuring a thickness of a specific portion on the substrate surface, and a step of calculating the thicknesses of all of the droplet given portions on the substrate surface on the basis of the measurement result.
Also, the above-described manufacturing method according to the present invention includes:
that the droplet given position is corrected by maintaining the distance between the ejecting portion and the droplet given surface on the substrate constant;
that the correction of the position to which the droplet is given is made by changing a timing at which the droplet is ejected from the ejecting portion in accordance with the distribution of the thickness of the substrate; or
that the correction of the position to which the droplet is given is made by changing an inclination of the substrate in accordance with the distribution of the thickness of the substrate.
Also, the above-described any manufacturing method according to the present invention includes:
that the droplet is given through an ink jet method;
that the ink jet method is of a system of giving a thermal energy to the liquid to produce a bubble, to thereby eject the droplet;
that the ink jet method is of a system of ejecting the droplet by a piezo-electric element;
that the electron source is an electron source including a plurality of electron emission element columns each having a plurality of electron emission elements connected between a pair of wirings; or
that the electron source is an electron source in which a plurality of electron emission elements are arranged in matrix by a plurality of row wirings and a plurality of column wirings.
Yet still further, according to the present invention, there is provided a method of manufacturing an image forming apparatus having an electron source and an image forming member onto which electrons are irradiated from the electron source, characterized in that the electron source is manufactured by any one of the above-described methods of manufacturing the electron source.
Yet still further, according to the present invention, there is provided a device of manufacturing an electronic device, characterized by comprising: an ejecting portion which ejects a droplet of a liquid containing a formation material of a member that constitutes the electronic device; means for relatively moving a substrate on which the electronic device is formed and the ejecting portion in an in-surface direction of the substrate; means for detecting a distance between the ejecting portion and a droplet given surface on the substrate; and means for controlling a position on the droplet given surface to which the droplet is given on the basis of the detection result.
Also, the above-described manufacturing device according to the present invention includes:
that the means for detecting the distance includes a mechanism for measuring the distances between the ejecting portion and all of the droplet given portions within the droplet given surface;
that the means for detecting the distance includes a mechanism for measuring a distance between the ejecting portion and a specific portion of the droplet given surface; or
that the means for detecting the distance includes a mechanism for measuring a distance between the ejecting portion and a specific portion of the droplet given surface, and a mechanism for calculating the distances between the ejecting portion and all of the droplet given portions within the droplet given surface on the basis of the measurement result.
Also, the above-described manufacturing device according to the present invention includes:
that the means for controlling the position to which the droplet is given includes a mechanism for maintaining the distance between the ejecting portion and the droplet given surface on the substrate constant;
that the means for controlling the position to which the droplet is given includes a mechanism for controlling a timing at which the droplet is ejected from the ejecting portion; or
that the means for controlling the position to which the droplet is given includes a mechanism for controlling an inclination of the substrate.
Yet still further, according to the present invention, there is provided a device of manufacturing an electronic device, characterized by comprising: an ejecting portion which ejects a droplet of a liquid containing a formation material of a member that constitutes the electronic device; means for relatively moving a substrate on which the electronic device is formed and the ejecting portion in an in-surface direction of the substrate; means for detecting a thickness of the substrate; and means for controlling a position on the substrate surface to which the droplet is given on the basis of the detection result.
Also, the above-described manufacturing device according to the present invention includes:
that the means for detecting the thickness includes a mechanism for measuring the thicknesses of all of the droplet given portions on the substrate surface;
that the means for detecting the thickness includes a mechanism for measuring a thickness of a specific portion on the substrate surface; or
that the means for detecting the thickness includes a mechanism for measuring a thickness of a specific portion on the substrate surface, and a mechanism for calculating the thicknesses of all of the droplet given portions on the substrate surface on the basis of the measurement result.
Also, the above-described manufacturing device according to the present invention includes:
that the means for controlling the droplet given position maintains the distance between the ejecting portion and the droplet given surface on the substrate constant;
that the means for controlling the position to which the droplet is given includes a mechanism for controlling a timing at which the droplet is ejected from the ejecting portion; or
that the means for controlling the position to which the droplet is given includes a mechanism for controlling an inclination of the substrate.
Also, the above-described any manufacturing device according to the present invention includes:
that the ejecting portion comprises a nozzle of an ink jet device;
that the ink jet device is of a system of giving a thermal energy to the liquid to produce a bubble, to thereby eject the droplet;
that the ink jet device is of a system of ejecting the droplet by a piezo-electric element;
that the electronic device comprises an electron source including a plurality of electron emission elements;
that the electron source comprises an electron source including a plurality of electron emission element columns having a plurality of electron emission elements connected between a pair of wirings;
that the electron source comprises an electron source in which a plurality of electron emission elements are arranged in matrix by a plurality of row wirings and a plurality of column wirings; or
that the electron emission element comprises an electron emission element including an electrically conductive film having an electron emission portion between a pair of electrodes.
The above-described electronic device according to the present invention includes, for example, a color filter of a liquid crystal display, a drive circuit of various displays such as a liquid crystal display, a plasma display or an electron ray display, an electron source per se, or the like. The structural member of the above electronic device manufactured by the manufacturing method and the manufacturing device according to the present invention is, particularly, a filter element in the above color filter, a drive electric conductor patterned on a circuit board or an insulator patterned on the circuit board for insulating between the drive electric conductors in the drive circuit for the above various displays, and an electric conductor that the structural member of a plurality of electron emission elements or the electron emission elements are connected to the drive wiring in the electron source, etc.
In the case where a droplet of a liquid containing a formation material of a member that constitutes the electronic device as described above is given to a plurality of portions on the substrate while the droplet ejecting portion and the substrate to which the droplet is given are relatively moved in an in-surface direction of the substrate, there is the distribution of the thickness of the substrate per se due to the unevenness of the thickness originally provided in the substrate or the distortion of the substrate which occurs in the manufacturing process until the droplet is given, or there is a case in which the flatness of a stage per se which holds the substrate when the droplet is given or the parallel degree of the ejecting portion and the substrate when the ejecting portion and the substrate are relatively moved is not constant. As a result, a distance between the substrate and the ejecting portion differs in each location on substrate (droplet given portion) to which the droplet is given, and the position to which the droplet is given (droplet given position) in fact is shifted from the above droplet given portion.
According to the manufacturing method of the present invention as described above, the droplet is given while the position on the droplet given surface to which the droplet is given is corrected in accordance with the distribution of the distances between the droplet ejecting portion and the droplet given surface on the substrate which occurs when the ejecting portion and the substrate are relatively moved in an in-surface direction of the substrate or while the position on the substrate surface to which the droplet is given is corrected in accordance with the distribution of the thickness of the substrate. As a result, the droplet can be given to a plurality of portions (droplet given portions) on the substrate to which the droplet is given with a high precision.
Also, in the manufacturing device according to the present invention, there are provided means for detecting a distance between the ejecting portion and a droplet given surface on the substrate, and means for controlling a position on the droplet given surface to which the droplet is given on the basis of the detection result; or means for detecting the thickness of the substrate, and means for controlling a position on the substrate surface to which the droplet is given on the basis of the detection result. As a result the above correction can be conducted, and the droplet can be given to a plurality of locations (droplet given portions) on the substrate to which the droplet is given with a high precision.
With the application of the above-described manufacturing method and manufacturing device according to the present invention, the color shift of the filter element can be prevented as much as possible in the above color filter, unnecessary shortcircuit between the drive electric conductors can be prevented as much as possible in the drive circuit of the above various displays, and the appearance of a defective electron emission element and non-uniformity of the characteristic can be prevented as much as possible in the electron source.